Fastening device for jewellery

ABSTRACT

Described is a fastening device for jewellery comprising a first element and a second element which can be fixed to respective ends of jewellery, wherein the first element has a top surface and a bottom surface, in which a socket is formed; the second element has a top surface, a bottom surface and a head, configured to interlock in a complementary way with the socket, so as to reversibly couple the first element with the second element; the second element comprises a groove, formed on its top surface, in which a sliding slider is housed, the first element comprises a recess, in a position adjacent to the socket, delimited by its top surface, so that, when the head is inserted in the socket, the slider remains in contact with the top surface of the first element at the recess, preventing the head from disengaging the socket and the second element from separating from the first element.

This invention relates to a fastening device for jewellery.

More specifically, the invention relates to a fastening device that can be used to wear bracelets, chains and the like in a more secure and easier way.

There are numerous and very different methods for fastening jewellery currently on the market.

By way of example, structurally unsophisticated fastening devices can be mentioned, such as simple hooks to be inserted in the end ring of a chain, or knots on opposite ends of a thread.

These types, however, offer a low level of solidity, in the first case, whilst in the second case they are difficult to fasten satisfactorily, as well as to unfasten.

More elaborate fastening devices are also known, equipped with locking elements operated by buttons.

Finally, much more common are the so-called “snap-hook” fastening devices, which provide a metal hook of various shapes and sizes, equipped with a spring element through which the fastening of the hook is ensured, which adopts, when closed, the characteristics of a loop.

A entire series of further variants have been derived from this last type, which mainly consist of an element which can be opened, fixed to one end of the support chain of the bracelet or necklace, and configured to lock the opposite one in a seat suitably formed inside it.

Amongst the main drawbacks these devices suffer from are:

-   -   the inconvenience and difficulty in opening and closing, as the         user is unable to use both hands to fasten the two ends of the         bracelet or necklace;     -   the fact that, when buttons or other similar elements must be         pressed to open the bracelet or chain, these are not always         easily accessible, and in addition, their very small dimensions         do not allow easy operation. It is also not uncommon for the         buttons to be operated accidentally;     -   the lack of solidity of the coupling, since the fastening         elements are composed of small and very thin parts and         consequently are not very resistant in case of impulsive forces;     -   in some cases, they make the appearance of the bracelet not very         homogeneous, as they interrupt the regularity of the succession         of decorative elements fixed to the chain or to the support         wire.

These and other drawbacks typical of the prior art are overcome by a fastening device with sliding operation, comprising two elements equipped with complementary profiles configured to engage and disengage each other, kept locked by a third element which allows them to be detached when operated.

The object of the invention is therefore a fastening device for jewellery comprising a first element and a second element which can be fixed to respective ends of jewellery, wherein the first element has a top surface and a bottom surface, in which a socket is formed; the second element has a top surface, a bottom surface and a head, configured to interlock in a complementary way with the socket, so as to reversibly couple the first element with the second element; the second element comprises a groove, formed on its top surface, in which a sliding slider is housed, the first element comprises a recess, in a position adjacent to the socket, delimited by its top surface, so that, when the head is inserted in the socket, the slider remains in contact with the top surface of the first element at the recess, preventing the head from disengaging the socket and the second element from separating from the first element.

Preferably, the device comprises an elastic means, and the groove comprises a closed end opposite the first element; the elastic means is positioned in the groove between the slider and the closed end, in such a way as to keep the slider in contact with the top surface of the first element when the device is closed.

In this way a more stable and more versatile hold of the fastening is obtained, being able to modulate the force with which the slider is moved according to the size of the spring.

Furthermore, the socket and the head have a taper in a direction that goes from the top surface to the bottom surface of the first and/or second element.

According to a further embodiment, a cover or an external containment casing, having a U-shape, covering the first element, the second element and the slider, can be included.

In this case, the casing or the cover can be integral with the slider, in such a way that their displacement caused by an external force causes the slider to slide inside the groove.

In addition, a guide can be provided inside the slider, in which a pin is housed which is integral with the second element, in such a way that a horizontal movement of the casing causes the slider to slide inside the groove.

According to a particular embodiment of the invention, the joint between the socket and the head is of the dovetail type.

Finally, the recess can also be obtained, according to alternative embodiments, between the two bottom and top surfaces of the first element.

This limits the accumulation of dirt and dust inside.

The invention will now be described by way of non-limiting examples according to some of its preferred embodiments, with the aid of the attached drawings, in which:

FIG. 1 is a perspective exploded view of an embodiment of the fastening device for jewellery according to the invention;

FIGS. 2A and 2B are perspective views of the device of FIG. 1 in a closed configuration;

FIGS. 3A and 3B are perspective views of the device of FIG. 1 in an open configuration;

FIG. 4 is a perspective cross section view along the plane A-A visible in FIG. 2A;

FIGS. 5A and 5B are detailed views of a second embodiment of the device according to the invention;

FIGS. 6A and 6B are perspective partial cross section views of the first embodiment of the device according to the invention.

The accompanying drawing show an embodiment of the fastening device 1 according to the invention, comprising a first element 10 and a second element 20, each having a body having a substantially prismatic shape.

The first and second elements 10, 20 are fixed to the respective ends of a bracelet or chain (not shown), and can be joined by means of a dovetail joint.

The actual coupling consists of a head 201 formed on the second element 20 and a socket 101 formed on the first element 10, complementary to each other in such a way that the head 201 engages the socket 101.

Each element 10, 20 has a respective top surface 110, 210 and bottom surface 120, 220.

The profiles of the socket 101 and of the head 201 are laterally tapered, in order to facilitate their insertion and removal, as will be described in detail below.

Thanks to this feature, moreover, it is possible to avoid clearances or loose joints between the parts.

In the bottom surface 120 of the first element 10 there is a recess 102 adjacent to, and communicating with, the socket 101; this recess 102 is delimited by the top surface 110 of the first element 10 itself, in such a way that it is visible only by observing it from the bottom surface 120.

According to an alternative embodiment of the device (shown in FIGS. 5A and 5B) the recess 102 is included between the top surface 110 and the bottom surface 120 of the first element 10.

In the top surface 210 of the second element 20 a substantially rectilinear groove 240 is formed in a longitudinal direction, provided with an open end facing towards the first element 10, while in the other end there is a blind wall 203.

Inside the groove 240 a slider 40 is slidably housed together with a spring 60.

The slider 40 has a tooth 402 (FIGS. 3A and 3B) and a relief 403, each at its respective ends. The tooth 402 faces the first element 10 protruding from the groove 240.

The relief 403 acts as an anchor point for the first end of the spring 60 on the slider 40, and the wall 203 acts as an anchor point for the second end of the spring 60 on the second element 20.

Moreover, a guide 401 is formed in the central body of the slider 40, to allow the sliding of a pin 50 relative to the slider 40 itself.

Externally, to cover the components described above, a casing 30 can be included.

The pin 50 is integral with the second element 20, and is inserted in the guide 401 and inside the casing 30 through a hole 350, formed on a side wall of the casing 30 itself.

The second element 20 has a cylindrical housing 250 inside its body in which the pin 50 is positioned after insertion.

The housing 250 is positioned transversely with respect to the groove 240 and passes through, in such a way that the pin 50 can intersect the guide 401 of the slider 40.

The pin 50 and the guide 401 thus form a prismatic joint, which limits the displacements of the slider 40, allowing only the translation along the groove 240.

The casing 30 internally comprises a seat 340 in which the slider 40 is housed and which, preferably, acts as a further blockage for the slider 40 itself.

Thus, this slider 40 is made integral with the casing 30, being able to be moved indirectly through an external action exerted on the casing 30 itself.

The operation of the device 1 is now described to better illustrate the mutual interaction between its component parts.

When the device 1 is in the closed configuration, the head 201 is housed in the socket 101; the spring 60 keeps the slider 40 in contact with the top surface 110 of the first element 10.

The casing 30 is connected to the slider 40 and can be moved only together with it.

This is important for the satisfactory operation of the device 1; in fact, it is possible to induce the separation of the two elements 10 and 20 simply by pulling them in opposite directions, due to the tapering of the socket 101 and the head 201.

The horizontal displacement of the two elements 10 and 20 therefore occurs simultaneously with a reciprocal vertical displacement, due to the inclination of the side surfaces in contact with the socket 101 and the head 201.

The slider 40 prevents the vertical displacement of the two elements 10 and 20, thus preventing accidental or unwanted detachment.

More specifically, the tooth 402, housed inside the recess 120, is pushed in contact with the top surface 110 of the first element 10 by the spring 60, and physically prevents detachment from the second element 20.

To allow the separation of the elements 10 and 20, and, therefore, the opening of the device 1, the slider 40 must be moved towards the wall 203 of the groove 240 and the spring 60 must be compressed.

This is possible thanks to the sliding of the casing 30 in the same direction; the casing 30 drags with it the slider 40 integral with it, moving it away from the first element 10.

The vertical movement between the two elements 10 and 20 is now allowed, the constraint represented by the tooth 402 of the slider 40 having been removed.

The casing 30 is set in motion by a force exerted by the user, and the same force is transmitted, through the slider 40, to the second element 20, inducing its separation from the first element 10.

If, on the other hand, it is necessary to close the device when it is open, the head 201 is inserted in the socket 101 and a slight pressure is applied.

The tooth 402 of the slider 40 encounters the opposition of the top surface 110 of the first element 10, which pushes it against the spring 60 and towards the wall 203 of the second element 20.

Once the head 201 and the socket 101 fit together, the device 1 adopts the closed configuration.

The fastening of the device 1 can take place only if the insertion of the head 201 into the socket 101 takes place from the side of the top surface 110 of the socket 101 itself.

Both the closing operation and the opening operation can be performed with a single hand, therefore in an easy and simple way with respect to the prior art.

Moreover, the absence of buttons or other systems which can sometimes be operated involuntarily makes the device according to the invention safer than the prior art.

Furthermore, the casing 30 which covers the other components of the device 1 can have an aesthetic as well as functional value, unlike prior art systems.

This invention is described by way of example only, without limiting the scope of application, according to its preferred embodiments, but it shall be understood that the invention may be modified and/or adapted by experts in the field without thereby departing from the scope of the inventive concept. 

1. Fastening device (1) for jewels comprising a first element (10) and a second element (20), connectable to respective ends of a jewel, wherein the first element (10) includes a top surface (110), and a bottom surface (120) provided with a socket (101), the second element (20) includes a top surface (210), a bottom surface (220) and a head (201), suitable to complementarily fit said socket (101), so as to reversibly join the first element (10) and the second element (20), characterized in that said second element (20) comprises a groove (240), carved on its top surface (210), in which a slider (40) is housed, and in that said first element (10) comprises a recess (102), adjacent to said recess (101) and delimited by the top surface (110), so that when the head (201) is inserted in the socket (101), the slider (40) reaches the mechanic stop with the top surface (110) of the first element (10) in correspondence with the recess (102), preventing the head (201) to disengage the socket (101) and the second element (20) to disjoin the first element (10).
 2. Fastening device (1) according to claim 1, characterized in comprising an elastic means (60), and in that said groove (240) has a closed end (203) opposed to said first element (10), wherein the elastic means (60) is placed in said groove (240) between the slider (40) and said closed end (203), so that the slider (40) reaches the mechanic stop with the top surface (110) of the first element (10) when the device (1) is fastened.
 3. Fastening device (1) according to claim 1 or 2, characterized in that said socket (101) and said head (201) are tapered in a direction going from the top surface (110) to the bottom surface (210) of said first (10) and/or second element (20).
 4. Fastening device (1) according to claim 1, characterized in comprising an external casing (30) for containment having a U shape and covering the first element (10), the second element (20) and the slider (40).
 5. Fastening device (1) according to claim 1, characterized in that said casing (30) is integrated with said slider (40), so that a displacement of the casing (30) elicited by an external force causes the sliding of the slider (40) in the groove (40).
 6. Fastening device (1) according to claim 4, characterized in that a guide (401) is built in said slider (40), a pin (50) integrated to the second element (20) being housed in said guide (401), so that an horizontal displacement of the casing (30) causes the sliding of the slider (40) in the groove (240).
 7. Fastening device (1) according to claim 1, characterized in that the joining between said socket (101) and said head (201) is a swallow tail-like joint.
 8. Fastening device (1) according to claim 1, characterized in that the recess (102) is delimited by the bottom surface (120) and by the top surface (110) of the first element (10). 